One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,3)(5,6)(7,10)(8,9)(11,12)(15,23)(16,22)(17,20)(19,24)(25,26)(27,28)(6,9)(7,11)(13,14)(15,19)(16,20)(17,22)(18,21)(23,24)(25,27)(26,28) involution — undirected(13,15,18,25)(14,19,21,27)(16,24,22,28)(17,26,20,23)(5,7,8,11)(6,10,9,12)(13,16,18,22)(14,20,21,17)(15,24,25,28)(19,23,27,26)(1,3,4,2)(6,9)(10,12)(14,21)(15,25)(16,22)(23,26)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.